Known reciprocating internal combustion piston engines generally comprise the follow structural characteristics: 1. A crank connecting rods structure, which comprises a engine body, pistons, connecting rod, and a crankshaft flywheel; 2. Valve structure, which comprises intake and exhaust valves and camshafts; 3. Fuel supply structure, which comprises a fuel tank, fuel pumps, and a carburetor (or a fuel nozzle); 4. Lubrication system, which comprises lubricating channel, oil pump, filter, and oil valve; 5. Cooling system which comprises a water tank, thermostat, water pump, cooling fan, and water sleeve; 7. Ignition system, which comprises a battery, electricity generator, distributor, ignition coil, and spark plug; 7 starting system, which comprises a starter motor. In accordance with the number of strokes required to complete a stroke loop, the reciprocating internal combustion piston engine can be categorized into four-stroke and two-stroke engine. The stroking loop for a four-stroke piston engine is: intake stroke—pistons move from the top most point to the lowest point, which suck in combustible gas (or air) into cylinders; compression stroke—pistons move from the lowest point to the top most point, which compress combustible gas (or air); power stroke—pistons move from the top most point to the lowest point, this is triggered by when pistons move to the top most point, spark plugs ignite (or fuel nozzle spray fuel into the cylinder, the compressed combustible gas burns in the combustion chamber, the high temperature and high pressure air expands in the chamber, which pushes the pistons from top to down; and exhaust stroke—pistons move from the lowest point to the top most point, which release the exhaust gas from burning the fuel out from the cylinder. The stroking loop for a two-stroke piston engine (gasoline engine) is: first stroke—pistons move from lowest point to the top most point, when the pistons are moving up, ventilation vent and exhaust vent close; when the ventilation vent and exhaust vent are closing, the mixed air and fuel that is already in the cylinder is compressed until the pistons are move to the top most point. In addition, when the pistons are moving upward, the volume of the crankcase increasing and creating a vacuum effect and when the pistons moves to the intake vent, the pistons are pull back into the crankcase. Second stroke—pistons move from top most point to the lowest point, this is triggered by when pistons move to the top most point, spark plugs ignite (or fuel nozzle spray fuel into the cylinder, the compressed combustible gas burns in the combustion chamber, the high temperature and high pressure air expands in the chamber, which pushes the pistons from top to down, and at the same time, turn the crankshaft to generate output force. In addition, when the pistons are moving downward, the mixed air and fuel in the crankcase is compressed, when the pistons move to the lowest point, the exhaust vent is open, the exhaust air from burning the fuel is release out from the cylinder by pressure, then the ventilation vent opens allowing the mixed air and fuel in the crankcase into the cylinder.
Whether it is a four-stroke internal combustion engine or a two-stroke internal combustion engine, they all based on the combustion of gasoline, diesel fuel and other combustible materials that can be mixed with air to form flammable compressed air that when burning, generates high temperature and high pressure air that expands in the cylinder, and pushes pistons from top most point to the lowest point to reach to generate force. However, one of biggest problem with this working principle is that: the high temperature and high pressured air generate from burning the mixed gas burning to generate expanding force in the valve is immediately released from the valve, as such the efficient use of heat energy is low and at the same time, pollutes the environment. In addition, the four-stroke internal combustion engine requires four strokes to complete a stroking loop, this require more complex gas distribution structure and a water cooling system, as such further increase the heat loss. On the other hand, although a two-stroke internal combustion engine has a simpler stroking loop requirement and structural characteristics, and the heat loss during the stroking loop is less than the four-stroke engine, however, because limited by the structural characteristics, the heat energy use efficiency may not be as better than a four-stroke engine. And finally, during the power stroke, the temperature in the cylinders may reach 2000 F to 2500 F, such high temperature may lead to fast wear of the engine components and greatly reduce the life of an engine. And production costs to manufacturer engine components that could withstand the high temperature are generally high.
In order to effectively use the heat energy and increase the efficiency of internal combustion engine, many improvement methods have been introduced. One method is to spray water into the cylinders. The principle of the water spraying method is that, when the engine is running, the high temperature inside the cylinders expands the water vapor and produces pressure that help to push the pistons. Typically, there are two types of water spray methods: first method is when the engine is running and when the pistons are moving from top most point to the lowest point, appropriate amount of water is sprayed into the cylinders. The high temperature inside the cylinders then immediately vaporize the water and the water vapor is expanded to produce added pressure that help to optimize engine work and discharge of exhaust gas. The second method is when pistons are completing the power stroke; where when pistons are moving from lowest point to the top most point to compress the remaining exhaust gas; when the pistons are moving close to the top most point, appropriate amount of water is then sprayed into the cylinders, and then the high temperature vaporizes the water and the water vapor is expanded to produce additional force to push the pistons downward to initiate a second power stroke.
The two water spray methods described above has some similarities and differences. One similarity is that both methods require a direct spray of water into cylinders and then the high temperature in the cylinder vaporize the water to increase engine work efficiency. One difference between the two methods is that in the first method, the water spray timing is selected at when pistons are completing the power stroke, and use the high temperature in the cylinder to vaporize the water to produce vapor pressure to provide auxiliary boost effect. And in the second method the water is sprayed when the pistons have completed the power stroke and are proceeding to and after the compression stroke. The second method uses the heat from cylinder, pistons, and gas to vaporize the water and produce vapor pressure to push the pistons to initiate a second stroking loop.
The above two water spray methods because of different water spray timing, there are shortcomings unique to each method. In the first method, because water is sprayed when the pistons are moving from lowest point to the top most point, only a small amount of water can be sprayed, otherwise it will impact normal working of the engine, as such the heat energy use is limited. In addition, because the water is sprayed during the stroking loop, therefore, when the engine is cold or during the high speed running, the first water spray may not have effective result. On the other hand, the second water spray method sprays water when the pistons have completed the power stroke, however, during this time, most of heat generated from burning the combustible gas have already released out from the cylinders, therefore, the water sprayed into the cylinder may not be fully turned into vapor pressure, as a result damaging the engine components. In addition, there is a greater temperature difference inside the cylinders and may reduce the life of the engine.